What is Mycat? __ Database

First, what is Mycat:
Mycat is an open source distributed database system, is a MySQL implementation of the server, front-end users can see it as a database agent, with the MySQL client tools and command line access, and the backend can use the MySQL native protocol with multiple MySQL server communication, You can also use the JDBC protocol to communicate with most of the mainstream database server, its core function is a partitioned library, will be a large table horizontally divided into n small tables, stored in the back-end MySQL server or other databases.

Mycat developed to the current version, is not a simple MySQL agent, its backend can support MySQL, SQL Server, Oracle, DB2, PostgreSQL and other mainstream databases, but also support MongoDB this new NoSQL way of storage, More types of storage will be supported in the future. And in the end user view, regardless of that kind of storage way, in Mycat, is a traditional database table, supports the standard SQL statement to carry on the data operation, thus, to the front-end business system, may reduce the development difficulty greatly, the promotion development speed

Second, then why to use the mycat it.

For example, the operating system is an abstraction of various kinds of computer hardware. So when do we need abstraction? If there is only one kind of hardware, we need to develop an operating system.
Another example is a project only need a person to complete the time does not need to leader, but when the need for dozens of people to complete, there should be a manager, play the role of communication and coordination, and this manager for his upper level is the project team abstraction.
Similarly, when our application needs only one database server, we do not need to mycat, and if you need a library or even a table, when the application to face a lot of databases, this time it is necessary to do an abstraction of the database layer to manage these databases, And the top of the application only need to face a database layer of abstraction or database middleware is good, this is the core role of Mycat.
So you can understand that the database is an abstraction of the underlying storage file, and Mycat is an abstraction of the database.